Operational and Test Performance in the Presence of Built-in Current Sensors

The effects of Built-In Current Sensors (BICS) on IDDQ measurements as well as on theperformance of the circuit under test are considered. Most of the Built-In Current Sensordesigns transform the ground terminal of the circuit under test into a virtual ground. Thiscauses increases in both propagation delay and IDDQ sampling time with the increase in thenumber of gates, affecting both test as well as operational performance. The effects thatcurrent sensors have on the operational and test performance of a circuit are considered.Circuit partitioning may be used for overcoming the effects of BICS on IDDQ measurementsas well as on the performance of the circuit under test